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| Started by | Huacai Chen <chenhc@lemote.com> |
|---|---|
| First post | 2017-09-13 11:30 +0200 |
| Last post | 2017-09-13 11:30 +0200 |
| Articles | 1 — 1 participant |
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[PATCH V3 3/3] scsi: Align queue to ARCH_DMA_MINALIGN in non-coherent DMA mode Huacai Chen <chenhc@lemote.com> - 2017-09-13 11:30 +0200
| From | Huacai Chen <chenhc@lemote.com> |
|---|---|
| Date | 2017-09-13 11:30 +0200 |
| Subject | [PATCH V3 3/3] scsi: Align queue to ARCH_DMA_MINALIGN in non-coherent DMA mode |
| Message-ID | <upc9B-5vh-21@gated-at.bofh.it> |
In non-coherent DMA mode, kernel uses cache flushing operations to maintain I/O coherency, so scsi's block queue should be aligned to ARCH_DMA_MINALIGN. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen <chenhc@lemote.com> --- drivers/scsi/scsi_lib.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9cf6a80..79433ad 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2132,11 +2132,14 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) q->limits.cluster = 0; /* - * set a reasonable default alignment on word boundaries: the - * host and device may alter it using + * set a reasonable default alignment on word/cacheline boundaries: + * the host and device may alter it using * blk_queue_update_dma_alignment() later. */ - blk_queue_dma_alignment(q, 0x03); + if (plat_device_is_coherent(dev)) + blk_queue_dma_alignment(q, 0x04 - 1); + else + blk_queue_dma_alignment(q, dma_get_cache_alignment() - 1); } EXPORT_SYMBOL_GPL(__scsi_init_queue); -- 2.7.0
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